Reinforced plastic sheet utility bag

ABSTRACT

A structurally enhanced plastic bag, comprising front and back plastic sheets interconnected along side edges and along a bottom edge, the sheets having unconnected top edges, at least one top edge defining an undulant upward protrusion along edge medial extents, the two sheets defining at least one transverse medial opening intersecting a portion of the protrusion to define a handle between the upper edge of the protrusion and the opening, and a structural plastic sheet patch bonded to at least one of the front and back sheets and extending proximate the transverse medial opening, and in upward alignment with the handle.

BACKGROUND OF THE INVENTION

This invention relates generally to plastic bags, and more particularly to structural enhancement of plastic bags having handles consisting of thin plastic sheet material.

Plastic bags, as for example are used for shopping purposes, typically have elongated, narrow strips of plastic handle material. Such material deforms into long narrow configurations, when such bags are filled and picked up for transport. The strips deformed into narrower configuration, are uncomfortable to handle since their narrow configurations tend to bite into the user's hand or hands. There is need for overcoming these disadvantages, and there is also need for improvements in bag and handle enhancement configurations which ease the transport of filled bags, and which also strengthen such bags without unduly adding to bulk of plastic bag material which is environmentally objectionable.

SUMMARY OF THE INVENTION

It is a major object of the invention to provide an enhanced plastic bag overcoming the above problems and disadvantages. Basically, the structurally enhanced plastic bag now provided by the invention comprises:

a) front and back plastic sheets interconnected along side edges and along a bottom edge, the sheets having unconnected top edges,

b) at least one top edge defining an undulant upward protrusion along edge medial extents,

c) the two sheets defining at least one transverse medial opening intersecting a portion of the protrusion to define a handle between the upper edge of the protrusion and said opening,

d) and a structural plastic sheet patch bonded to at least one of the front and back sheets and extending proximate said transverse medial opening, and in upward alignment with said handle.

In this regard, it is important that each sheet have its own handle, including spaced handle arms, and patch reinforcement of such arms.

As will be seen, the plastic sheet patch is confined to an area of the flat sheet bag side which is less than ⅓ of the total side area, thereby providing structural strength and stability, without interfering with bag use including flexibility, and without adding unduly to total plastic bag sheet volume or area, for environmental compliance.

It as another object of the invention to configure the improved plastic bag in such manner that the transverse opening has a cross dimension of at least 4 centimeters, and preferably between 4 and 5 centimeters in the bag with direction.

A further object is to configure the structurally enhanced bag so as to locate the bulk of the sheet patch between lowermost and uppermost levels of the transverse opening. In this regard, the bulk of the sheet patch in one configuration lies between a lower level below the lowermost level of said opening, and an upper level above the uppermost level of said opening.

Yet another object is to structurally configure the plastic bag so as to locate the upper protrusion defined by said one of the front and back sheets has laterally spaced angled upper edges in lateral alignment with uppermost extent of the sheet patch. In this regard the laterally spaced upper edges typically extend angularly toward uppermost extent of the protrusion and above the sheet patch for optimum strength of the improved bag and handle.

An added object is to provide an undulant or wavy laterally extending uppermost edge, for added structural strength, distributing loading between the handle and bag front and back sheets.

Additional objects include provision of sheet patch glue bonding to one of the sheets, everywhere at one side of the sheet patch; provision of two of the sheet patches respectively bonded to the two sheets at the inner sides thereof that face the bag interior; provision of sheet patch translucence in matching relation to translucence of the two bag sheets for concealment of the sheet patches at the inner sides of the two sheets; and provision of sheet patch laterally lengthwise extent throughout the laterally length dimensions of both said transverse opening and the major lateral length of the undulant top edge forming handle or handles of the two sheets.

A yet further object is to provide the plastic bag to have bag folded bottom sheet edge area wall thickness to substantially increase overall bag wall thickness along its bottom edge for enhanced load carrying structural strength, directly below the handle wavy top edge and below the strength enhancing sheet patch or patches, as referred to.

Another object is to provide bag handle left and right upright extents to which the patch is bonded generally laterally of said opening.

These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which:

DRAWING DESCRIPTION

FIG. 1 is a side elevation showing one form reinforced preferred plastic bag incorporating the invention;

FIG. 2 is an enlarged section taken on lines 2-2 of FIG. 1;

FIG. 3 is an enlarged section taken on lines 3-3 of FIG. 1;

FIG. 4 is a side elevation showing another form of the enhanced structural strength bag with top wavy edge oriented relative to a plastic patch which in turn extends above the level of a transverse opening;

FIG. 5 is an enlarged section taken on lines 5-5 of FIG. 4;

FIG. 6 is an enlarged section taken on lines 6-6 of FIG. 4;

FIG. 7 is a side elevation showing yet another form of the enhanced structural strength bag with reinforcing;

FIG. 8 is an enlarged section taken on lines 8-8 of FIG. 7;

FIG. 9 is an enlarged section taken on lines 9-9 of FIG. 7; and

FIGS. 10 and 11 are side elevations showing yet further forms of reinforced plastic bags incorporating aspects of the invention.

DETAILED DESCRIPTION

Referring first to FIGS. 1-3, they show a structurally enhanced plastic bag 10 that comprises front and back flexible plastic sheets 10 a and 10 b interconnected along upright side edges at 11 and 12, and along a laterally horizontal bottom edge area 13. The sheets have unconnected top edges 14 and 15 which complementarily are wavy or undulant. See left and right concave edges at 16 and 17, and merging with upwardly convex top edge 18, which is spaced above a transverse opening or hole 19 through the sheets. Concave edges 16 and 17 are spaced laterally from the uppermost extent of opening 19. The illustrated structure defines an upward protrusion in the form of a handle 20 confined or spaced from side edges 11 and 12, thereby defining bag and handle upper edges that remain open for transported, projecting goods 22 and 23, without interference with manual gripping of the handle and finger protrusion through the transverse generally circular opening 19. See also handle upright left and right load path defining extents 20 a and 20 b, adjacent concave edges 16 and 17. Accordingly, at least one sheet top edge, but preferably both define undulant left and right protrusions along top edge medial extent or extents; and the transverse opening intersects the handle left and right protrusions.

Of importance is the provision of a structural plastic sheet patch 30 everywhere surface-to-surface bonded, as for example by glue or adhesive, or heat sealed, at interface 35 to at least one of the front and back sheets, and to extend proximate the transverse medial opening 19, and in upward alignment with the handle 20. Note that the patch is generally rectangular, having upper and lower edges 31 and 32, and laterally spaced edges 33 and 34 proximate the concave edges 16 and 17 of the two sheets. Upper edge 31 extends above the levels of 16 and 17 and laterally intersects the convex top edge 18. Preferably two such patches are provided, at the inner sides of the two sheets and handles. They provide reinforcement for loading imposed by carried goods, along two patches indicated by arrows 37 and 38, as when upward force is manually transmitted at 39. Such load transition paths extend laterally as well as downwardly.

In FIG. 1, the opening 19 typically has a cross-dimension, as for example diameter, between about 4 and 5 centimeters, in width dimension, in bag upright position. Also the bulk of the patch 30 is at about the level of opening 19, i.e. as shown, the bulk of the patch lies to the left and to the right of the opening, for reinforcement of both handle 20 and bag sheet material about 19.

Further, the two sheets 11 and 12, and the patch 30 may consist of translucent flexible plastic sheet material for concealment of the sheet patches at the inner sides of the two sheets. The bag sheets can be of any color, opaque or translucent.

Provision of the patch, and its relation to the bag handle, its wavy upper edge, and in relation to the transverse opening 19, facilitate non-crumpling re-use of the lightweight bag over extended re-use periods, which contribute to desirable environmental efforts and objectives, i.e. obviating one-time use throw-away construction of contemporary plastic bags which easily crumple during one-time use. Thus, the plastic bag of the invention has shape retaining attributes of paper bags.

FIG. 3 shows that the bag 10 has folded sheet bottom edge area enhanced wall thickness for substantially increasing overall bag thickness along the bag bottom edge, for enhancement of load carrying structural strength of the bag and for bag shape retention, desirably below the strength enhancing sheet patch and below the handle upper undulant edge that promotes load distribution laterally. See upward folds at 10 a′ and 10 b′ of sheets 10 a and 10 b, at the inner side of 10 a and 10 b, so that the bottom area 40 of the bag is sturdily reinforced for transporting heavier loads, the bag tending to keep its shape. See also bonding at 10 c.

FIGS. 4-6 are like FIGS. 1-3, except that the modified plastic patch 50 extends principally above the transverse opening 19′ and above the levels of concave edges 16′ and 17′. The patch extends vertically to the dome-like top of the upper undulant edge 18′ so that the patch upper edge is also wavy or undulant, for reinforcing of the handle uppermost extent. The upright lateral edges 33′ and 34′ of the patch are located to the left and right of the top of opening 19′, but below the convex dome extent of the handle upper edge. Like patches 50 may be used at the inner sides of both of the bag handle extents associated with the two sheets 11′ and 12′. FIGS. 5 and 6 are like FIGS. 2 and 3.

In FIGS. 7-9, the modified plastic patch 60 (or patches) has curved upper and lower edges 60 a and 60 b, and laterally spaced curved edges 60 c and 60 d. The latter sub-tend and match the convex curvature of the wavy handle 20″ upper convex edge 18″. Lower edge 60 b intersects circular through opening 19″ as shown, and upper edge 60 a is spaced below the dome crest. Accordingly, the main extent of the undulant handle, with two load path defining handle arms 20 a″ and 20 b″, is reinforced. Also, and as shown, each thin patch is dimpled, at 64, and over its area for added stiffening, contributing to strength and bag shape retention, under loading in the plane of the patch. The patches are bonded to inner sides of bag sheets 10 a″ and 10 b″.

Reinforcement of the bag lower extent 40″ includes sheet in-turned folds at 10 a″-1 and 10 b″-1 which may be bonded together at 66.

In FIG. 10 a laterally elongated finger-grip opening 70 extends through two like plastic bag sides 71, and below the top edge 72 of handle 73, that protrudes at 74 above the opening. Plastic patch 75 is bonded to the handle, to have its elongated lower edge 76 located just below the opening, its top edge 77 co-terminal with the handle upper edge 72, and its lateral edges 78 and 79 located to the left and right ends respectively of the opening.

FIG. 11 shows a bag, handle and patch configuration 80 similar to that of FIG. 4, and the same identifying numerals are used.

In the above, the sheet thickness of the bag sides and handles is between 8 microns and 200 microns. The patch may have the same or similar thickness. Usable plastic materials include polyethylene. 

1. A structurally enhanced plastic bag, comprising in combination: a) front and back plastic sheets interconnected along side edges and along a bottom edge, the sheets having unconnected top edges, b) at least one top edge defining an undulant upward protrusion along edge medial extents, c) the two sheets defining at least one transverse medial opening intersecting a portion of the protrusion to define a handle between the upper edge of the protrusion and said opening, d) and a structural plastic sheet patch bonded to at least one of the front and back sheets and extending proximate said transverse medial opening, and in upward alignment with said handle.
 2. The combination of claim 1 wherein said transverse opening has a cross dimension between four and five centimeters, in bag upright position.
 3. The combination of claim 1 wherein the bulk of said sheet patch is above the level of said opening.
 4. The combination of claim 1 wherein the bulk of the sheet patch lies between the lowermost and the uppermost levels of said opening.
 5. The combination of claim 1 wherein the bulk of the sheet patch lies between a lower level below the lowermost level of said opening, and an upper level above the uppermost level of said opening.
 6. The combination of claim 1 wherein the sheet patch is everywhere bonded to said one of the sheets, by x₁) glue, x₂) heat sealing.
 7. The combination of claim 1 wherein there are two of said sheet patches respectively bonded to the two sheets at the inner sides thereof that face the bag interior.
 8. The combination of claim 7 wherein said sheet patches and the two sheets consist of translucent flexible plastic sheet material for concealment of the sheet patches at the inner sides of the two sheets.
 9. The combination of-claim 8 wherein the sheet patches extend laterally lengthwise throughout the lateral length dimensions of both said transverse opening and the major lateral length of the undulant top edges of the two sheets.
 10. The combination of claim 1 wherein the bag has folded sheet bottom edge area enhanced wall thickness for substantially increasing overall bag thickness along the bag bottom edge for enhancement of load carrying structural strength of the bag desirably below the strength enhancing sheet patch and below the handle upper undulant edge.
 11. The combination of claim 1 wherein the bag one sheet defines handle left and right upright extents to which the patch is bonded generally laterally of said opening.
 12. The combination of claim 1 wherein the patch is dimpled for added strength under loading extended along a path or paths in the plane of the patch.
 13. The combination of claim 1 wherein protrusion defined by said one of the front and back sheets has laterally spaced angled upper edges in lateral alignment with uppermost extent of the sheet patch.
 14. The combination of claim 6 wherein said laterally spaced upper edges extend angularly toward uppermost extent of the protrusion.
 15. The combination of claim 11 wherein the bag has an uppermost edge which is laterally undulant above the level of the sheet patch.
 16. The bag of claim 13 wherein said patch is bonded to said at least one of the front and back sheets by one of the following: x₁) glue, x₂) heat sealing.
 17. The bag of claim 1 wherein sheet thickness is between 8 and 200 microns. 